Scenario
Our scenario builds off of our persona, Aly, from GR1. Aly is an MIT sophomore who has a flight home to Florida at the end of the semester, on May 17th at 6 AM. She always buys cheap flights, which often leave in the early morning before the public transportation system operates, as is the case for this particular flight, so she wishes to take a cab to the airport. Aly uses RideShare to find people to share a cab with her for this flight. The tasks she needs to perform are:
- Search for a ride share
- Post a new RideShare listing for her desired time and destination
- Invite friends to see her RideShare post
Design
Our final design (shown above) consists of a few main parts: the header, the 'find a ride' panel, the 'post a ride' panel, and the rides listing (which can either show all rides or just the users rides). We decided on a minimalist design in which all of the site's functionality is plainly visible on the main page, including the functions of searching, posting new rides, and viewing ride posting. We did this to improve efficiency and visibility for the user. 
The user can interact with the 'Find a Ride' panel to filter rides according to three distinctions: Purpose, Date, and Time. Since we expect that the total number of rides on the site will be pretty low at any given time, we did not include a search for location. It isn't necessary and the user might feel like they have to know exactly where they're going. It is easier to have them browse ride listed for the category they are interested in.
Filters are applied right when the user adds or changes them (using ajax). We decided to do this because it gives the user immediate feedback. During paper prototyping, we considered using a standard form with a search button or having a filter button for each category, but testing made it apparent that immediate ajax response was the best option and made the most sense to most users.
When filters are applied, the user is shown a message that contains the tags they are searching for (as in the above image). The user can easily clear all search filters by using the standard 'x'.
Ride listings are laid out as shown above, with an icon to indicate category, a bolded origin and destination, and color-coded date and time information. Rides are laid out to convey the information as clearly as possible, using different visual variables to distinguish between fields. Using the different colored icons helps users locate rides of different categories more easily. The most important information, origin and destination, is the largest and darkest text so that the user will see that first.
If a ride belongs to a user, an 'X' is added in the top right corner so that the post can be removed (all of a user's rides can be found by clicking the 'your rides' tab). 
Each ride also has a 'share via email' and 'join ride' (if the ride belongs to someone else) link. When clicked, the above dialog pops up so that the user can contact the poster or share the ride with friends. 
To add a new ride to the listing, a user can fill out the 'post a ride' form, shown above.